Diaphragm Pump with Automatic Priming Function

ABSTRACT

Illustrative embodiments of diaphragm pumps having an automatic priming function, as well as related systems and methods, are disclosed. In one illustrative embodiment, a method of priming a diaphragm pump includes sensing, with a pressure sensor disposed at a fluid outlet of the diaphragm pump, a pressure of a fluid being pumped by the diaphragm pump, transmitting a pressure signal associated with the sensed pressure from the pressure sensor to a controller of the diaphragm pump, and identifying, on the controller, whether the diaphragm pump is primed by determining whether a characteristic of the pressure signal has reached a threshold.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/763,926, filed on Feb. 11, 2013, which is incorporated herein byreference in its entirety.

TECHNICAL FIELD

The present disclosure relates, generally, to diaphragm pumps and, moreparticularly, to diaphragm pumps having an automatic priming function.

BACKGROUND

Diaphragm pumps may occasionally be disconnected from their fluidsources. Upon reconnecting the pump, it must be primed in order toremove air from the plumbing connections and to prepare the pump forimmediate delivery of pumped fluid when operated. Prior pump systemshave typically implemented a priming function by operating the pump fora set period of time. Such priming functions, however, do not reliablyachieve prime. For instance, the pump may not actually achieve primeduring the set period of time, in which case the priming function hasfailed. Alternatively, the pump may achieve prime before the end of theset period of time, in which case excess fluid will be pumped downstreamand wasted.

SUMMARY

According to one aspect, a pump system may comprise a diaphragm pumpincluding (i) a shaft coupled to a diaphragm and configured to movereciprocally between a first end-of-stroke position and a secondend-of-stroke position, (ii) a stroke sensor configured to sense whetherthe shaft has reached one of the first and second end-of-strokepositions, (iii) a pressure sensor disposed at a fluid outlet of thediaphragm pump and configured to sense a pressure of a fluid pumped bythe diaphragm pump, and (iv) a solenoid valve configured to controlsupply of a motive fluid that causes the shaft to move between the firstand second end-of-stroke positions; and a controller communicativelycoupled to the diaphragm pump and configured to (i) identify whether theshaft has reached one of the first and second end-of-stroke positionsusing a stroke signal received from the stroke sensor, (ii) identifywhether the diaphragm pump is primed by determining whether acharacteristic of a pressure signal received from the pressure sensorhas reached a threshold, and (iii) transmit a control signal to thesolenoid valve in response to identifying that the shaft is in one ofthe first and second end-of-stroke positions and that the diaphragm pumpis not primed, the control signal actuating the solenoid valve such thatthe motive fluid causes the shaft to move between the first and secondend-of-stroke positions.

In some embodiments, the controller may be configured to determinewhether the characteristic of the pressure signal has reached thethreshold by determining whether at least one of a differential, anaverage, a rolling average, a peak value, and an amplitude of thepressure signal has reached the threshold. The controller may beconfigured to determine whether the characteristic of the pressuresignal has reached the threshold in response to identifying that theshaft has reached one of the first and second end-of-stroke positions.

In some embodiments, the controller may be further configured to track anumber of strokes of the shaft using the stroke signal received from thestroke sensor and transmit the control signal to the solenoid valve inresponse to identifying (i) that the shaft is in one of the first andsecond end-of-stroke positions, (ii) that the diaphragm pump is notprimed, and (iii) that the number of strokes of the shaft has notexceeded a stroke limit. The controller may be configured to transmitthe control signal to the solenoid valve in response to identifying (i)that the shaft is in one of the first and second end-of-strokepositions, (ii) that the diaphragm pump is not primed, and (iii) that atimer of the controller has not exceeded a time limit.

According to another aspect, a method of priming a diaphragm pump mayinclude sensing whether a shaft coupled to a diaphragm has reached anend-of-stroke position using a stroke sensor of the diaphragm pump;identifying, on a controller of the diaphragm pump, whether the shaft isin the end-of-stroke position using a stroke signal generated by thestroke sensor; sensing a pressure of a pumped fluid at a fluid outlet ofthe diaphragm pump using a pressure sensor disposed at the fluid outlet;identifying, on the controller, whether the diaphragm pump is primed bydetermining whether a characteristic of a pressure signal generated bythe pressure sensor has reached a threshold; and actuating a solenoidvalve, in response to identifying that the shaft is in the end-of-strokeposition and that the diaphragm pump is not primed, to cause a motivefluid to be supplied to the diaphragm such that the shaft moves from theend-of-stroke position.

In some embodiments, actuating the solenoid valve may include actuatingthe solenoid valve in response to identifying (i) that the shaft is inthe end-of-stroke position, (ii) that the diaphragm pump is not primed,and (iii) that a number of strokes of the shaft has not exceeded astroke limit. The method may further include executing, on thecontroller, an alarm protocol in response to identifying that thediaphragm pump is not primed and that the number of strokes of the shafthas exceeded the stroke limit.

In some embodiments, actuating the solenoid valve may include actuatingthe solenoid valve in response to identifying (i) that the shaft is inthe end-of-stroke position, (ii) that the diaphragm pump is not primed,and (iii) that a timer of the controller has not exceeded a time limit.The method may further include executing, on the controller, an alarmprotocol in response to identifying that the diaphragm pump is notprimed and that the timer of the controller has exceeded the time limit.Determining whether the characteristic of the pressure signal hasreached the threshold may include determining whether at least one of adifferential, an average, a rolling average, a peak value, and anamplitude of the pressure signal has reached the threshold.

According to yet another aspect, a method of priming a diaphragm pumpmay include sensing, with a pressure sensor disposed at a fluid outletof the diaphragm pump, a pressure of a fluid being pumped by thediaphragm pump; transmitting a pressure signal associated with thesensed pressure from the pressure sensor to a controller of thediaphragm pump; and identifying, on the controller, whether thediaphragm pump is primed by determining whether a characteristic of thepressure signal has reached a threshold.

In some embodiments, the method may further include ceasing to pump thefluid with the diaphragm pump in response to identifying that thediaphragm pump is primed. The method may further include pumping fluidat a non-uniform flow rate, with the diaphragm pump, through the fluidoutlet in response to identifying that the diaphragm pump is not primed.The method may further include pumping fluid, with the diaphragm pump,through the fluid outlet in response to identifying that the diaphragmpump is not primed and that a timer of the controller has not exceeded atime limit. The method may further include ceasing to pump the fluidwith the diaphragm pump in response to identifying that the timer of thecontroller has exceeded the time limit.

In some embodiments, the method may further include tracking, on thecontroller, a number of strokes of a shaft of the diaphragm pump andpumping fluid, with the diaphragm pump, through the fluid outlet inresponse to identifying that the diaphragm pump is not primed and thatthe number of strokes has not exceeded a stroke limit. The method mayfurther include ceasing to pump the fluid with the diaphragm pump inresponse to identifying that the number of strokes has exceeded thestroke limit. The method may further include executing, on thecontroller, an alarm protocol in response to identifying that thediaphragm pump is not primed and that the number of strokes has exceededthe stroke limit. Determining whether the characteristic of the pressuresignal has reached the threshold may include determining whether atleast one of a differential, an average, a rolling average, a peakvalue, and an amplitude of the pressure signal has reached thethreshold.

BRIEF DESCRIPTION OF THE DRAWINGS

The concepts described in the present disclosure are illustrated by wayof example and not by way of limitation in the accompanying figures. Forsimplicity and clarity of illustration, elements illustrated in thefigures are not necessarily drawn to scale. For example, the dimensionsof some elements may be exaggerated relative to other elements forclarity. Further, where considered appropriate, reference labels havebeen repeated among the figures to indicate corresponding or analogouselements.

FIG. 1 is a front perspective view of at least one embodiment of adouble diaphragm pump;

FIG. 2 is a cross-sectional view of the pump of FIG. 1, taken along theline 2-2 in FIG. 1;

FIG. 3 is a simplified block diagram of at least one embodiment of apump system including the pump of FIGS. 1 and 2;

FIG. 4 is a simplified flow diagram of at least one embodiment of amethod of priming the pump of FIGS. 1 and 2; and

FIGS. 5A and 5B are a simplified flow diagram of at least one otherembodiment of a method of priming the pump of FIGS. 1 and 2.

DETAILED DESCRIPTION OF THE DRAWINGS

While the concepts of the present disclosure are susceptible to variousmodifications and alternative forms, specific exemplary embodimentsthereof have been shown by way of example in the drawings and willherein be described in detail. It should be understood, however, thatthere is no intent to limit the concepts of the present disclosure tothe particular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the present disclosure.

Referring now to FIGS. 1 and 2, a diaphragm pump 10 is shown. The pump10 of FIGS. 1 and 2 is illustratively embodied as a double-diaphragmpump. It is contemplated that, in other embodiments, the pump 10 may beembodied as any other type of diaphragm pump. In the illustrativeembodiment, the pump 10 has a housing 12 that defines a first workingchamber 14 and a second working chamber 16. In the illustrativeembodiment, the housing 12 is comprised of three sections coupledtogether by fasteners. As best seen in FIG. 2, the first and secondworking chambers 14, 16 of the pump 10 are each divided with respectivefirst and second flexible diaphragms 18, 20 into respective first andsecond pump chambers 22, 24 and first and second motive fluid chambers26, 28. The diaphragms 18, 20 are interconnected by a shaft 30, suchthat when the diaphragm 18 is moved to increase the volume of theassociated pump chamber 22, the other diaphragm 20 is simultaneouslymoved to decrease the volume of the associated pump chamber 24, and viceversa.

The shaft 30 illustrated in FIG. 2 is a reciprocating diaphragm link rodhaving a fixed length, such that the position of the shaft 30 in thepump 10 is indicative of the position of the diaphragms 18, 20. Theshaft 30 and diaphragms 18, 20 move back and forth a fixed distance thatdefines a stroke. The fixed distance is determined by the geometry ofthe pump 10, the shaft 30, the diaphragms 18, 20, and other componentsof the pump 10 (e.g., the diaphragm washers). A stroke is defined as thetravel path of the shaft 30 between first and second end-of-strokepositions. Movement of the shaft 30 from one end-of-stroke position tothe other end-of-stroke position and back defines a cycle of operationof the shaft 30 (i.e., a cycle includes two consecutive strokes).

The pump 10 includes an inlet 32 for the supply of a motive fluid (e.g.,compressed air, or another pressurized gas) and a major valve 34 foralternately supplying the motive fluid to the first and second motivefluid chambers 26, 28 to drive reciprocation of the diaphragms 18, 20and the shaft 30. When the major valve 34 supplies motive fluid to themotive fluid chamber 26, the major valve 34 places an exhaust assembly36 in communication with the other motive fluid chamber 28 to permitmotive fluid to be expelled therefrom. Conversely, when the major valve34 supplies motive fluid to the motive fluid chamber 28, the major valve34 places the motive fluid chamber 26 in communication with the exhaustassembly 36. In the illustrative embodiment of the pump 10, movement ofthe major valve 34 between these positions is controlled by a solenoidvalve 44. As such, by controlling movement of the major valve 34, thesolenoid valve 44 of the pump 10 controls the supply of the motive fluidto the first and second motive fluid chambers 26, 28.

The exhaust assembly 36 of the pump 10 includes an exhaust chamber 50and a muffler 52 that is received in the exhaust chamber 50. The exhaustassembly 36 may have a design similar to the exhaust system described inU.S. patent application Ser. No. 13/741,057 to Treml et al., the entiredisclosure of which is incorporated by reference herein. In theillustrative embodiment shown in FIG. 2, the muffler 52 includes asensor mounting chamber 54 formed therein, and a stroke sensor 56 isdisposed within the sensor mounting chamber 54. The stroke sensor 56 isillustratively embodied as a proximity sensor that detects the presenceor absence of material (or a particular type of material) within acertain distance of the sensor. The shaft 30 may include one or morefeatures that are detectable by the stroke sensor 56 when the shaft 30reciprocates between the first and second end-of-stroke positions. Inthe illustrative embodiment shown in FIG. 2, the shaft 30 includes acentral notch 58 where the shaft 30 has a smaller diameter. In thisembodiment, the stroke sensor 56 will not be triggered when the shaft 30is in a centered position within the pump 10 (i.e., the position shownin FIG. 2), as no material is present within the sensing field of thestroke sensor 56. As the shaft 30 moves toward one of the end-of-strokepositions, the material of a larger diameter portion of the shaft 30will enter the sensing field of the stroke sensor 56 and trigger thestroke sensor 56. Other possible configurations for the shaft 30 thatmay be sensed by the stroke sensor 56 are described in U.S. PatentApplication Publication No. 2010/0196168 to Kozumplik et al., the entiredisclosure of which is incorporated by reference herein.

It is contemplated that, in other embodiments of the pump 10, the strokesensor 56 may be any type of sensor capable of sensing whether the shaft30 has reached one of the first and second end-of-stroke positions andmay be positioned in any number of locations within the pump 10. Forinstance, in some embodiments, the stroke sensor 56 may be a pressureswitch fluidly coupled to a pilot valve (not shown) of the pump 10. Insuch embodiments, the stroke sensor 56 may measure a pressure at thepilot valve of the pump 10 to determine whether the shaft 30 has reachedone of the first and second end-of-stroke positions. In still otherembodiments of the pump 10, the stroke sensor 56 may be embodied as anoptical sensor capable of sensing whether the shaft 30 has reached oneof the first and second end-of-stroke positions. It will be appreciatedthat the foregoing examples (i.e., a proximity sensor, a pressuresensor, and an optical sensor) are merely illustrative and should not beseen as limiting the stroke sensor 56 to any particular type of sensor.

During operation of the pump 10, as the shaft 30 and the diaphragms 18,20 reciprocate, the first and second pump chambers 22, 24 alternatelyexpand and contract to create respective low and high pressure withinthe respective first and second pump chambers 22, 24. The pump chambers22, 24 each communicate with an inlet manifold 38 that may be connectedto a source of fluid to be pumped and also each communicate with anoutlet manifold, or fluid outlet, 40 that may be connected to areceptacle for the fluid being pumped. Check valves (not shown) ensurethat the fluid being pumped moves only from the inlet manifold 38 towardthe outlet manifold 40. For instance, when the pump chamber 22 expands,the resulting negative pressure draws fluid from the inlet manifold 38into the pump chamber 22. Simultaneously, the other pump chamber 24contracts, which creates positive pressure to force fluid containedtherein into the outlet manifold 40. Subsequently, as the shaft 30 andthe diaphragms 18, 20 move in the opposite direction, the pump chamber22 will contract and the pump chamber 24 will expand (forcing fluidcontained in the pump chamber 24 into the outlet manifold 40 and drawingfluid from the inlet manifold 38 into the pump chamber 24). The pump 10also includes a pressure sensor 42 connected to, or forming a part of,the outlet manifold 40. The pressure sensor 42 may be embodied as anytype of sensor capable of determining a pressure of a fluid being pumpedthrough the fluid outlet 40.

Referring now to FIG. 3, one illustrative embodiment of a pump system100 including the pump 10 of FIGS. 1 and 2 and a controller 102 is shownas a simplified block diagram. As described above, the pump 10 mayinclude a solenoid valve 44, a pressure sensor 42, and a stroke sensor56. In the illustrative embodiment shown in FIG. 3, the controller 102is communicatively coupled to the solenoid valve 44, the pressure sensor42, and the stroke sensor 56 of the pump 10 via one or more wiredconnections 118. In other embodiments, the controller 102 may becommunicatively coupled to the solenoid valve 44, the pressure sensor42, and the stroke sensor 56 via other types of connections (e.g.,wireless or radio links). It should be appreciated that, in someembodiments, the controller 102 may constitute a part of the pump 10.The controller 102 is, in essence, the master computer responsible forinterpreting signals sent by sensors associated with the pump 10 and foractivating or energizing electronically-controlled components associatedwith the pump 10. For example, the controller 102 is configured tomonitor various signals from the pressure sensor 42 and the strokesensor 56, to control operation of the solenoid valve 44, and todetermine when various operations of the pump system 100 should beperformed, amongst many other things. In particular, as will bedescribed in more detail below with reference to FIGS. 4, 5A, and 5B,the controller 102 is operable to identify whether the pump 10 isprimed.

To do so, the controller 102 includes a number of electronic componentscommonly associated with electronic control units utilized in thecontrol of electromechanical systems. In the illustrative embodiment,the controller 102 of the pump system 100 includes a processor 110, aninput/output (“I/O”) subsystem 112, a memory 114, and a user interface116. It will be appreciated that the controller 102 may include other oradditional components, such as those commonly found in a computingdevice (e.g., various input/output devices). Additionally, in someembodiments, one or more of the illustrative components of thecontroller 102 may be incorporated in, or otherwise form a portion of,another component of the controller 102 (e.g., as with amicrocontroller).

The processor 110 of the controller 102 may be embodied as any type ofprocessor capable of performing the functions described herein. Forexample, the processor may be embodied as one or more single ormulti-core processors, digital signal processors, microcontrollers, orother processors or processing/controlling circuits. Similarly, thememory 114 may be embodied as any type of volatile or non-volatilememory or data storage device capable of performing the functionsdescribed herein. The memory 114 stores various data and software usedduring operation of the controller 102, such as operating systems,applications, programs, libraries, and drivers. For instance, the memory114 may store instructions in the form of a software routine (orroutines) which, when executed by the processor 110, allows thecontroller 102 to control operation of the pump 10. The user interface116 permits a user to interact with the controller 102 to, for example,initiate an automatic priming function of the pump system 100. As such,in some embodiments, the user interface 116 includes a keypad, touchscreen, display, and/or other mechanisms to permit I/O functionality.

The memory 114 and the user interface 116 are communicatively coupled tothe processor 110 via the I/O subsystem 112, which may be embodied ascircuitry and/or components to facilitate I/O operations of thecontroller 102. For example, the I/O subsystem 112 may be embodied as,or otherwise include, memory controller hubs, I/O control hubs, firmwaredevices, communication links (e.g., point-to-point links, bus links,wires, cables, light guides, printed circuit board traces, etc.), and/orother components and subsystems to facilitate the I/O operations. In theillustrative embodiment, the I/O subsystem 112 includes ananalog-to-digital (“A/D”) converter, or the like, that converts analogsignals from the pressure sensor 42 and the stroke sensor 56 of the pump10 into digital signals for use by the processor 110. It should beappreciated that, if any one or more of the sensors associated with thepump 10 generate a digital output signal, the A/D converter may bebypassed. Similarly, in the illustrative embodiment, the I/O subsystem112 includes a digital-to-analog (“D/A”) converter, or the like, thatconverts digital signals from the processor 110 into analog signals foruse by the solenoid valve 44 of the pump 10. It should also beappreciated that, if the solenoid valve 44 operates using a digitalinput signal, the D/A converter may be bypassed.

Referring now to FIG. 4, one illustrative embodiment of a method 200 ofpriming the pump 10 of FIGS. 1 and 2 is shown as a simplified flowdiagram. The method 200 represents one illustrative embodiment of anautomatic priming function of the pump 10 and the pump system 100. Themethod 200 may be initiated by a user of the pump system 100 (forinstance, by selecting an appropriate input on the user interface 116 ofthe controller 102) or may be initiated by the controller 102 withoutuser input. The method 200 is illustrated in FIG. 4 as a number ofblocks 202-210, which may be performed by various components of the pumpsystem 100 of FIG. 3.

The method 200 begins with block 202 in which the controller 102transmits a control signal to the pump 10 that causes the pump 10 topump fluid through the fluid outlet 40. Due to the mechanics of thediaphragm pump 10 described above, the pump 10 may pump fluid at adiscontinuous or otherwise non-uniform flow rate, unlike many othertypes of pumps. As such, in some embodiments, pumping fluid through thefluid outlet 40 in block 202 may comprise transmitting a control signalfrom the controller 102 to the solenoid valve 44 that causes a singlestroke of the pump 10. In other embodiments, block 202 may comprisecycling the pump 10 at least once. It will be appreciated that, untilthe pump 10 has achieved prime, the fluid being pumped through the fluidoutlet 40 in block 202 will be air (and not the fluid supplied to theinlet manifold 38 of the pump 10).

After block 202, the method 200 proceeds to block 204 in which the fluidpressure at the fluid outlet 40 of the pump 10 is determined using thepressure sensor 42. In other words, the pressure sensor 42 of the pump10 senses the pressure of the fluid being pumped through the fluidoutlet 40 and generates a pressure signal associated with the sensedpressure. The pressure sensor 42 may transmit this pressure signal tothe controller 102 continuously or intermittently, including, by way ofexample, in response to a query from the controller 102. It iscontemplated that the block 204 may be performed continuously orintermittently during performance of the method 200 (including duringthe block 202).

After block 204, the method 200 proceeds to block 206 in which thecontroller 102 determines whether the pump 10 is primed. In theillustrative embodiment, the controller 102 uses the pressure signalgenerated by the pressure sensor 42 in block 204 to identify whether thepump 10 is primed. In particular, block 206 may involve block 208 inwhich the controller 102 determines whether a characteristic of thepressure signal received from the pressure sensor 42 has reached athreshold. When the pump 10 reaches prime (i.e., when air has been fullypurged from the pump 10 and the fluid supplied to the inlet manifold 38reaches the fluid outlet 40), the pressure signal generated by thepressure sensor 42 will have a substantially different signature thanthe pressure signal associated with an unprimed pump 10. As such,various pressure signal characteristics may be used to distinguishbetween a primed and unprimed state of the pump 10. For example, adifferential (i.e., rate of change) of the pressure signal, an averageof the pressure signal, a rolling average of the pressure signal, a peakvalue of the pressure signal, and/or an amplitude of the pressure signalmay be compared to a threshold in block 208. When one or more of thesecharacteristics of the pressure signal generated by the pressure sensor42 reaches (or passes) one or more thresholds, the controller 102 mayidentify the pump 10 as primed. It is contemplated that any number ofpressure signal characteristics may be used in block 208, so theillustrative characteristics listed above should not be regarded aslimiting.

After block 206, the method 200 proceeds to block 210 in which thecontroller 102 determines whether to continue or conclude the method 200(i.e., the automatic priming function). If the controller 102 determinedin block 206 that the pump 10 was not primed, block 210 may involve thecontroller 102 returning the method 200 to block 202. As such, in theillustrative embodiment of FIG. 4, the method 200 will be repeated untilthe pump 10 has achieved prime. If the controller 102 instead determinedin block 206 that the pump 10 was primed, the controller 102 willconclude the method 200 in block 210. In some embodiments, concludingthe method 200 in block 210 may involve the diaphragm pump 10 ceasing topump fluid through the fluid outlet 40 without losing prime. It will beappreciated that this is not possible in many other types of pumps(e.g., continuous flow pumps) because ceasing to pump fluid will resultin a loss of prime. In other embodiments, concluding the method 200 inblock 210 may allow the controller 102 to proceed to another controlalgorithm or function.

Referring now to FIGS. 5A and 5B, one illustrative embodiment of amethod 300 of priming the pump 10 of FIGS. 1 and 2 is shown as asimplified flow diagram. The method 300 represents another illustrativeembodiment of an automatic priming function of the pump 10 and the pumpsystem 100. Like the method 200, the method 300 may be initiated by auser of the pump system 100 (for instance, by selecting an appropriateinput on the user interface 116 of the controller 102) or may beinitiated by the controller 102 without user input. The method 300 isillustrated in FIGS. 5A and 5B as a number of blocks 302-322, which maybe performed by various components of the pump system 100 of FIG. 3.While the illustrative embodiment of method 300 shown in FIGS. 5A and 5Butilizes both a timer of the controller 102 and a stroke signalgenerated by the stroke sensor 56 of the pump 10, it is contemplatedthat other embodiments of the method 300 may utilize only one of thesefeatures. It will be appreciated that, in such alternative embodimentsof the method 300, certain of the blocks 302-322 (or portions thereof)may not be included in the method 300.

The method 300 begins with block 302 in which the controller 102initializes a timer and/or a stroke counter for use in “timing out” themethod 300 (i.e., the automatic priming function). In the illustrativeembodiment of method 300, a timer of the controller 102 is used to trackhow long the automatic priming function has been running (e.g., inminutes, seconds, milliseconds, or some other measure of time). Asdescribed further below, the method 300 may conclude (and/or otheraction may be taken) if the timer reaches a time limit prior to the pump10 reaching prime. Similarly, a stroke counter may be used by thecontroller 102 to count a number of strokes of the shaft 30 of the pump10. As described further below, the method 300 may conclude (and/orother action may be taken) if the stroke counter reaches a stroke limitprior to the pump 10 reaching prime. As mentioned above, someembodiments of the method 300 may involve only one of the timer and thestroke counter (and not the other).

After block 302, the method 300 proceeds to block 304 in which thecontroller 102 transmits a control signal to actuate the solenoid valve44. As discussed above, actuation of the solenoid valve 44 causesmovement of the major valve 34, which supplies motive fluid to one ofthe motive fluid chambers 26, 28 of the pump 10, thereby stroking thepump 10 (i.e., moving the shaft 30 and diaphragms 18, 20 from oneend-of-stroke position to the other end-of-stroke position) and causingfluid to be pumped through the fluid outlet 40. It will be appreciatedthat, until the pump 10 has achieved prime, the fluid being pumpedthrough the fluid outlet 40 in block 202 will be air (and not the fluidsupplied to the inlet manifold 38 of the pump 10).

After block 304, the method 300 proceeds to block 306 in which thecontroller 102 determines whether the shaft 30 has reached one of theend-of-stroke positions. In other words, the controller 102 identifieswhether the shaft 30 has moved from one end-of-stroke position to theother end-of-stroke position. In the illustrative embodiment shown inFIG. 5A, block 306 involves block 308 in which the stroke sensor 56(e.g., a proximity sensor, as shown in FIG. 2) senses a position of theshaft 30 and generates a stroke signal associated with the sensedposition. In other embodiments, as discussed above, block 306 mayinvolve another type of stroke sensor 56 (e.g., a pressure sensor, anoptical sensor, etc.) generating a stroke signal that indicates whetherthe shaft 30 has reached one of the end-of-stroke positions. The strokesensor 56 may transmit this stroke signal to the controller 102continuously or intermittently, including, by way of example, inresponse to the shaft 30 reaching one of the end-of-stroke positions.

After block 306, the method 300 proceeds to block 310 in which thecontroller 102 determines whether to repeat the block 306 or continuethe method 300. If the controller 102 determined in block 306 that theshaft 30 had yet not reached one of the end-of-stroke positions, block310 may involve the controller 102 returning the method 300 to block306. As such, in the illustrative embodiment of FIG. 5A, blocks 306-310will be repeated until the shaft 30 is in one of the end-of-strokepositions. If the controller 102 instead determined in block 306 thatthe shaft 30 had reached one of the end-of-stroke positions, the method300 will proceed to block 312 in which the controller 102 increments thestroke counter.

After block 312, the method 300 proceeds to block 314 in which the fluidpressure at the fluid outlet 40 of the pump 10 is determined using thepressure sensor 42. In other words, the pressure sensor 42 of the pump10 senses the pressure of the fluid being pumped through the fluidoutlet 40 and generates a pressure signal associated with the sensedpressure. The pressure sensor 42 may transmit this pressure signal tothe controller 102 continuously or intermittently, including, by way ofexample, in response to a query from the controller 102. It iscontemplated that the block 314 may be performed continuously orintermittently during performance of the method 300 (including duringother blocks of the method 300).

After block 314, the method 300 proceeds to block 316 in which thecontroller 102 determines whether the pump 10 is primed. In theillustrative embodiment, the controller 102 uses the pressure signalgenerated by the pressure sensor 42 in block 314 to identify whether thepump 10 is primed. In particular, block 316 may involve block 318 inwhich the controller 102 determines whether a characteristic of thepressure signal received from the pressure sensor 42 has reached athreshold. During blocks 316, 318, the controller 102 may performsimilar determinations to those described above with reference to blocks206, 208 of FIG. 4.

After block 316, the method 300 proceeds to block 320 in which thecontroller 102 determines whether to continue or conclude the method 300(i.e., the automatic priming function). If the controller 102 determinedin block 316 that the pump 10 was not primed, block 320 may result inthe method 300 proceeding to block 322 (described below). If thecontroller 102 instead determined in block 316 that the pump 10 wasprimed, the controller 102 will conclude the method 300 in block 320. Insome embodiments, concluding the method 300 in block 320 may involve thediaphragm pump 10 ceasing to pump fluid through the fluid outlet 40without losing prime. Once again, it will be appreciated that this isnot possible in many other types of pumps (e.g., continuous flow pumps)because ceasing to pump fluid will result in a loss of prime. In otherembodiments, concluding the method 300 in block 320 may allow thecontroller 102 to proceed to another control algorithm or function.

If the method 300 is not concluded in block 320, the method 300 proceedsto block 322 in which the controller 102 determines whether the value ofthe timer has reached a time limit and/or whether the value of thestroke counter has reached a stroke limit (and, thus, whether tocontinue or conclude the method 300). As noted above, the time limitand/or the stroke limit may be used by the controller 102 to prevent theautomatic priming function from executing perpetually. Such limits maybe implemented to, for example, prevent unnecessary damage or wear tothe pump 10. If the controller 102 determines in block 322 that theneither the time limit nor the stroke limit has been reached, block 322may involve the controller 102 returning the method 300 to block 304 (inwhich the controller 102 transmits a control signal to actuate thesolenoid valve 44 and stroke the pump 10). As such, in the illustrativeembodiment of FIGS. 5A and 5B, the method 300 will be repeated until thepump 10 has achieved prime, the time limit has been reached, or thestroke limit has been reached. If the controller 102 instead determinesin block 322 that the time limit (where used) has been reached or thatthe stroke limit (where used) has been reached, the controller 102 willconclude the method 300 in block 322. In some embodiments, block 322 mayalso involve the controller 102 executing an alarm protocol in responseto determining that time limit and/or stroke limit has been reached. Thealarm protocol may include, by way of example, displaying a warningmessage on the user interface 116 of the controller 102 and/or ceasingto pump fluid with the pump 10.

While certain illustrative embodiments have been described in detail inthe figures and the foregoing description, such an illustration anddescription is to be considered as exemplary and not restrictive incharacter, it being understood that only illustrative embodiments havebeen shown and described and that all changes and modifications thatcome within the spirit of the disclosure are desired to be protected.There are a plurality of advantages of the present disclosure arisingfrom the various features of the apparatus, systems, and methodsdescribed herein. It will be noted that alternative embodiments of theapparatus, systems, and methods of the present disclosure may notinclude all of the features described yet still benefit from at leastsome of the advantages of such features. Those of ordinary skill in theart may readily devise their own implementations of the apparatus,systems, and methods that incorporate one or more of the features of thepresent disclosure.

1. A pump system comprising: a diaphragm pump including (i) a shaftcoupled to a diaphragm and configured to move reciprocally between afirst end-of-stroke position and a second end-of-stroke position, (ii) astroke sensor configured to sense whether the shaft has reached one ofthe first and second end-of-stroke positions, (iii) a pressure sensordisposed at a fluid outlet of the diaphragm pump and configured to sensea pressure of a fluid pumped by the diaphragm pump, and (iv) a driveconfigured to cause the shaft to move between the first and secondend-of-stroke positions; and a controller communicatively coupled to thediaphragm pump and configured to (i) identify whether the shaft hasreached one of the first and second end-of-stroke positions using astroke signal received from the stroke sensor, (ii) identify whether thediaphragm pump is primed by determining whether a characteristic of apressure signal received from the pressure sensor has reached athreshold, and (iii) transmit a control signal to the drive in responseto identifying that the shaft is in one of the first and secondend-of-stroke positions and that the diaphragm pump is not primed, thecontrol signal actuating the drive such that the drive causes the shaftto move between the first and second end-of-stroke positions.
 2. Thepump system of claim 1, wherein the controller is configured todetermine whether the characteristic of the pressure signal has reachedthe threshold by determining whether at least one of a differential, anaverage, a rolling average, a peak value, and an amplitude of thepressure signal has reached the threshold.
 3. The pump system of claim1, wherein the controller is configured to determine whether thecharacteristic of the pressure signal has reached the threshold inresponse to identifying that the shaft has reached one of the first andsecond end-of-stroke positions.
 4. The pump system of claim 1, whereinthe controller is further configured to: track a number of strokes ofthe shaft using the stroke signal received from the stroke sensor; andtransmit the control signal to the drive in response to identifying (i)that the shaft is in one of the first and second end-of-strokepositions, (ii) that the diaphragm pump is not primed, and (iii) thatthe number of strokes of the shaft has not exceeded a stroke limit. 5.The pump system of claim 1, wherein the controller is configured totransmit the control signal to the drive in response to identifying (i)that the shaft is in one of the first and second end-of-strokepositions, (ii) that the diaphragm pump is not primed, and (iii) that atimer of the controller has not exceeded a time limit.
 6. A method ofpriming a diaphragm pump, the method comprising: sensing whether a shaftcoupled to a diaphragm has reached an end-of-stroke position using astroke sensor of the diaphragm pump; identifying, on a controller of thediaphragm pump, whether the shaft is in the end-of-stroke position usinga stroke signal generated by the stroke sensor; sensing a pressure of apumped fluid at a fluid outlet of the diaphragm pump using a pressuresensor disposed at the fluid outlet; identifying, on the controller,whether the diaphragm pump is primed by determining whether acharacteristic of a pressure signal generated by the pressure sensor hasreached a threshold; and actuating a drive, in response to identifyingthat the shaft is in the end-of-stroke position and that the diaphragmpump is not primed, to cause the shaft to move from the end-of-strokeposition.
 7. The method of claim 6, wherein actuating the drivecomprises actuating the drive in response to identifying (i) that theshaft is in the end-of-stroke position, (ii) that the diaphragm pump isnot primed, and (iii) that a number of strokes of the shaft has notexceeded a stroke limit.
 8. The method of claim 7, further comprisingexecuting, on the controller, an alarm protocol in response toidentifying that the diaphragm pump is not primed and that the number ofstrokes of the shaft has exceeded the stroke limit.
 9. The method ofclaim 6, wherein actuating the drive comprises actuating the drive inresponse to identifying (i) that the shaft is in the end-of-strokeposition, (ii) that the diaphragm pump is not primed, and (iii) that atimer of the controller has not exceeded a time limit.
 10. The method ofclaim 9, further comprising executing, on the controller, an alarmprotocol in response to identifying that the diaphragm pump is notprimed and that the timer of the controller has exceeded the time limit.11. The method of claim 6, wherein determining whether thecharacteristic of the pressure signal has reached the thresholdcomprises determining whether at least one of a differential, anaverage, a rolling average, a peak value, and an amplitude of thepressure signal has reached the threshold.
 12. A method of priming adiaphragm pump, the method comprising: sensing, with a pressure sensordisposed at a fluid outlet of the diaphragm pump, a pressure of a fluidbeing pumped by the diaphragm pump; transmitting a pressure signalassociated with the sensed pressure from the pressure sensor to acontroller of the diaphragm pump; and identifying, on the controller,whether the diaphragm pump is primed by determining whether acharacteristic of the pressure signal has reached a threshold.
 13. Themethod of claim 12, further comprising ceasing to pump the fluid withthe diaphragm pump in response to identifying that the diaphragm pump isprimed.
 14. The method of claim 12, further comprising pumping fluid ata non-uniform flow rate, with the diaphragm pump, through the fluidoutlet in response to identifying that the diaphragm pump is not primed.15. The method of claim 12, further comprising pumping fluid, with thediaphragm pump, through the fluid outlet in response to identifying thatthe diaphragm pump is not primed and that a timer of the controller hasnot exceeded a time limit.
 16. The method of claim 15, furthercomprising ceasing to pump the fluid with the diaphragm pump in responseto identifying that the timer of the controller has exceeded the timelimit.
 17. The method of claim 12, further comprising: tracking, on thecontroller, a number of strokes of a shaft of the diaphragm pump; andpumping fluid, with the diaphragm pump, through the fluid outlet inresponse to identifying that the diaphragm pump is not primed and thatthe number of strokes has not exceeded a stroke limit.
 18. The method ofclaim 17, further comprising ceasing to pump the fluid with thediaphragm pump in response to identifying that the number of strokes hasexceeded the stroke limit.
 19. The method of claim 17, furthercomprising executing, on the controller, an alarm protocol in responseto identifying that the diaphragm pump is not primed and that the numberof strokes has exceeded the stroke limit.
 20. The method of claim 12,wherein determining whether the characteristic of the pressure signalhas reached the threshold comprises determining whether at least one ofa differential, an average, a rolling average, a peak value, and anamplitude of the pressure signal has reached the threshold.